经度
jīng dù · HSK 7
longitude
🌐 经 (warp threads, running lengthwise) + 度 (degree) = longitude
经 — silk radical 纟 + 巠 (underground stream)
Originally written 經, combining the silk radical 糸 with 巠, depicting vertical threads on a loom. The core meaning was 'warp threads,' which extended to 'pass through,' 'classic text,' and 'manage.' The phonetic 巠 also suggests the sound.
度 — 广 (shelter) + 庶 abbreviated (phonetic)
Originally depicted a hand measuring length under a shelter, meaning 'to measure' or 'a measure/standard.' From this came extended senses like 'degree,' 'extent,' and 'to pass through' (as in passing time). The reading 'dù' means degree/measure, while 'duó' preserves the older verbal sense of measuring.